1. Technical Field
The present invention is directed toward window locks, and more particularly toward a sealing window lock including a pivoting handle for securing a window sash to a window frame.
2. Background Art
Window locks are, of course, well known. One common window lock type uses a handle pivotally mounted to a housing which is itself mounted to the window frame, and a keeper is mounted to the movable window sash. The handle may be manually pivoted to move a grasping member into and out of engagement with the keeper to lock or release the window sash as desired.
Handle locks of the type mentioned above typically include an opening in the housing through which the grasping member portion of the handle extends. There is therefore a risk of an undesirable energy loss if a draft develops through the housing opening around the handle. Further, light might pass through the opening and around the handle which, even though if occurring when the window sash is open to otherwise let in air and light, nevertheless creates a visual impression that the lock and/or window are of low quality construction. Still further, there is also the possibility that insects might pass through the opening and into the room interior.
Several lock structures have been created to address this problem. One locking handle has included a shoulder associated with the handle and abutting the bottom portion of the housing (that is, the portion below the pivot axis) when closed. The top portion of the housing includes an arcuate pocket adjacent the handle portion above the pivot axis in order to substantially close the opening at that upper end. However, because the pivot axis is offset from the visible surface of the housing, the handle portion above the pivot axis is necessarily rounded to cooperate with the arcuate pocket. As a result, there is a recess beneath the plane of the visible housing surface at the rounded end which detracts from the visually clean lines of the structure. Further, while the rounded end and the arcuate pocket block any straight path for air, light and/or insects, some spacing is required in order to allow the handle to pivot without binding and that spacing could still result in some air draft therethrough. Still further, the arcuate pocket results in a configuration which requires that the pivot holes in the housing be created by drilling therethrough, a step which naturally adds to the time and therefore cost of manufacture
Another locking handle structure which addresses the problems associated with space between a locking handle and housing is disclosed in Guelck U.S. Pat. No. 4,674,777. In this structure, the pivot for the handle is offset from the housing opening so that a shoulder may be freely carried with the handle and surround the housing opening to provide a seal when the handle is in a locking position. This structure can, however, leave a significant open space through the housing when the shoulder is not seated. Further, the feel of such a lock is somewhat unusual to a person operating it due to the unusual position of its pivot axis.
The present invention is directed toward overcoming one or more of the problems set forth above.